mat2listw: Convert a square spatial weights matrix to a weights list...
In spdep: Spatial Dependence: Weighting Schemes, Statistics

mat2listw

R Documentation

Convert a square spatial weights matrix to a weights list object

Description

The function converts a square spatial weights matrix, optionally a sparse matrix to a weights list object, optionally adding region IDs from the row names of the matrix, as a sequence of numbers 1:nrow(x), or as given as an argument. The style can be imposed by rebuilting the weights list object internally.

Usage

mat2listw(x, row.names = NULL, style=NULL, zero.policy = NULL)

Arguments

`x`	A square non-negative matrix with no NAs representing spatial weights; may be a matrix of class “sparseMatrix”
`row.names`	row names to use for region IDs
`style`	default NULL, missing, set to "M" and warning given; if not "M", passed to `nb2listw` to re-build the object
`zero.policy`	default NULL, use global option value; if FALSE stop with error for any empty neighbour sets, if TRUE permit the weights list to be formed with zero-length weights vectors

Value

A listw object with the following members:

`style`	"M", meaning matrix style, underlying style unknown, or assigned style argument in rebuilt object
`neighbours`	the derived neighbours list
`weights`	the weights for the neighbours derived from the matrix

Author(s)

Roger Bivand Roger.Bivand@nhh.no

Examples

columbus <- st_read(system.file("shapes/columbus.gpkg", package="spData")[1], quiet=TRUE)
col005 <- dnearneigh(st_coordinates(st_centroid(st_geometry(columbus),
 of_largest_polygon=TRUE)), 0, 0.5, as.character(columbus$NEIGNO))
summary(col005)
col005.w.mat <- nb2mat(col005, style="W", zero.policy=TRUE)
try(col005.w.b <- mat2listw(col005.w.mat, style="W"))
col005.w.b <- mat2listw(col005.w.mat, style="W", zero.policy=TRUE)
summary(col005.w.b$neighbours)
diffnb(col005, col005.w.b$neighbours)
col005.w.mat.3T <- kronecker(diag(3), col005.w.mat)
col005.w.b.3T <- mat2listw(col005.w.mat.3T, style="W", zero.policy=TRUE)
summary(col005.w.b.3T$neighbours)
run <- FALSE
if (require("spatialreg", quiet=TRUE)) run <- TRUE
if (run) {
W <- as(nb2listw(col005, style="W", zero.policy=TRUE), "CsparseMatrix")
try(col005.spM <- mat2listw(W))
col005.spM <- mat2listw(W, style="W", zero.policy=TRUE)
summary(col005.spM$neighbours)
}
if (run) {
diffnb(col005, col005.spM$neighbours)
}
if (run && require("Matrix", quiet=TRUE)) {
IW <- kronecker(Diagonal(3), W)
col005.spM.3T <- mat2listw(as(IW, "CsparseMatrix"), style="W", zero.policy=TRUE)
summary(col005.spM.3T$neighbours)
}

spdep documentation built on Sept. 13, 2024, 5:07 p.m.